nwrec container workshop i 2006
TRANSCRIPT
Jim Owen, Jr.
Substrate Properties: How to measure and manage them
North Willamette Research andExtension Center
My Approach
NUTRIENTS
ENVIRONMENT IRRIGATION
SUBSTRATE
ContainerContainer
My Approach
NUTRIENTS
ENVIRONMENT IRRIGATION
SUBSTRATEContainerContainer
My Approach
Engineer a substrate to balance water and air content
while providing or retaining plant nutrients
My Approach
SUBSTRATEWater : Air
“There is no one fit”
My Approach
SUBSTRATEWater : Air
SUMMERWater
WINTERAir
Approach
SUBSTRATEWater : Air
SUMMERWater
WINTERAir
My Approach
STABILITY OVER TIME
Optimal air and water characteristics
Decomposition / shrinkage during growing season
Initial vs end of season physical analysis
Supply and/or retain nutrients
Substrate
Total porosity (% volume)Air spaceContainer capacity
• Syn. water holding capacity
Terms
Total porosity (% volume)Air spaceContainer capacity
• Syn. water holding capacity Available water Unavailable water
Terms
Total porosity (% volume)Air spaceContainer capacity
• Syn. water holding capacity Available water Unavailable water
Bulk density (g cm-3)
Terms
Total porosity 50% - 85%Air space 10% - 30%Container capacity 45% - 65%
• Syn. water holding capacity Available water 25%- 30% Unavailable water 25%- 30%
Bulk density0.2 to 0.5 g cm-3
12 to 32 lbs ft-2
Terms
Gravitational waterDrainage water
Hygroscopic waterAdsorbed water
Capillary waterAvailable waterUnavailable water
Terms cont…
adsorbed or hygroscopic water
capillary water
Hillel
AIR : WATERRELATIONSHIP
Will a given substrate have a greater, equal, or less than
container capacity when compared to a field capacity?
Will a given substrate have a greater, equal, or less than container capacity when
compared to a field capacity?
WHY?
Water will not move from small pores (fine texture) to large pores (coarse texture) until small pores are saturated.
Small pores large pores
Small pores (full) large pores
Water movement
X
Sand over clay
Water movement
Oklahoma State University
Sand over clay
Water movement
Oklahoma State University
Clay over sand
Water movement
Oklahoma State University
Clay over sand
Water movement
Oklahoma State University
Moisture Content
Fonteno
Does container shape affect physical properties?
SOLIDS
WATER
AIR TOTAL POROSITY
Effected by container sizeAir space Container capacity
• Available water contentUnaffected by container size
Total PorosityUnavailable water contentBulk density
Physical Properties
SOLIDS
WATER
AIR TOTAL POROSITY
1 2 3Bilderback and Fonteno
29% 29% 29%
SOLIDS
WATER
AIR TOTAL POROSITY
1 2 3Bilderback and Fonteno
29% 29% 29%
SOLIDS
WATER
47% 45% 41%
AIR TOTAL POROSITY
1 2 3Bilderback and Fonteno
29% 29% 29%
SOLIDS
WATER
47% 45% 41%
AIR
24% 26% 30%
TOTAL POROSITY
1 2 3Bilderback and Fonteno
29% 29% 29%
SOLIDS
WATER
47% 45% 41%
AIR
24% 26% 30%
71% 71% 71%
TOTAL POROSITY
1 2 3Bilderback and Fonteno
Particle Size
Particle Size
Capillary Water
Particle SizeStabilityComponents “fit”Fine particles
< 0.5 mm Single component
• ≈ 25% by weightMultiple components
• < 50% by weight
Particle Size
05
10
15
20
25
30
35
40
% w
eigh
of p
artic
les
<
0.5
mm
Fresh PB Aged PB Fresh 8 PB: 1 Sand
Aged 8 PB :1 Sand
Particle Size
0
20
40
60
80
100
0.01 0.1 1 10 100Tension (kPa)
Perc
ent v
olum
e
Peat BarkCoir Perlite
Fonteno
Particle Size
0
20
40
60
80
100
0.01 0.1 1 10 100Tension (kPa)
Perc
ent v
olum
e
Peat BarkCoir Perlite
RAW
Fonteno
Particle Size
0
20
40
60
80
100
0.01 0.1 1 10 100Tension (kPa)
Perc
ent v
olum
e
Peat BarkCoir Perlite
EAWWBC
SUBSTRATE COMPONENTS
Primary ComponentDouglas Fir Bark
Secondary ComponentsPerlitePeatCoir
Tertiary ComponentsMineralsCompost
Northwest Substrate
First, I Digress!
Bark Inventory Management
Bark SupplyCheck interior of inventory piles
Pour thru Saturate media extract
Desired resultspH > 3.8EC < 0.5 mmhos
Bark Supply
Bark Arrives Hot! Steam Haze around pile! Spores
Bark SupplyMoisture Content- By feel or %weight
Bark should not be powder drySmell; Vinegar smell could be trouble;
indicates anaerobic conditionsAcetic acid lowers pH and extracts
saltspH can be as low as 2.3EC can be as high as 2.5 mmhos/ cm
Bark SupplyMycelium
Gray colorGray bandDry pocketsHydrophobioc
Turn and moisten pile
Bark SupplyBe prepared not to immediately use bark
supplies if monitoring suggests problemsDevelop an inventory storage area and
wet and turn piles 2-3 days before useAlways check pH and EC before using
stored suppliesConsider blending old inventory and new
inventory (50:50)
Douglas Fir Bark
Altland
Douglas Fir Bark
AGED FRESH
Altland
Douglas Fir Bark
0%
20%
40%
60%
80%
100%
Con
tain
er V
olum
e
Fresh bark Aged bark Recommendedrange
WaterAirSolid
Buamscha and Altland
Douglas Fir Bark
0%
20%
40%
60%
80%
100%
Con
tain
er V
olum
e
Fresh bark Aged bark Recommendedrange
WaterAirSolid
Water Holding Capacity
27% 37% 45% - 65%
Buamscha and Altland
50% 35% 10% - 30%
Volcanic rockBendMazama – Crater lake
High porosity Water holding capacity ~30%Chemical
SiO2
Neutral pHBase cations and Fe-oxides
Pumice
Buamscha and Altland
Industrial mineral AggregateChemical absorbentFertilizer carrierBarrier clays
Murray, 2000.
Mineral aggregateRaw Clay Selection & Mining
Primary CrusherSecondary Crusher
Dryer(RVM)Mill
Screen
Rotary Kiln(LVM)
Oil-Dri Corporation of America
Bag or Bulk
≤ 800°C ≈ 120°C
Mineral aggregate
Zeolite
Mineral aggregate
Shulze, D.G., 2002. An introduction to soil mineralogy. In: Soil Mineralogy with Environmental Applications SSSA Book Series no. 7.
Mineral AggregateMontmorillonite Palygorskite
Shulze, D.G., 2002. An introduction to soil mineralogy. In: Soil Mineralogy with Environmental Applications SSSA Book Series no. 7.
Amendment
Montmorillonite Palygorskite
Surface Area ≈ 90 m2/gCEC ≈ 100 cmolc kg
Oil-Dri Corporation of America
Clinoptilolite
Surface Area ≈ 40 m2/gCEC ≈ 250 cmolc kg
Surface Area ≈ 120 m2/gCEC ≈ 20 cmolc kg
Amendment
Shulze, D.G., 2002. An introduction to soil mineralogy. In: Soil Mineralogy with Environmental Applications SSSA Book Series no. 7.
HeatingDehydration
Natural Occurring
LowVolatileMaterial
Palygorskite and Zeolite
Amendment
HeatingDehydration
Natural Occurring
LowVolatileMaterial
Shulze, D.G., 2002. An introduction to soil mineralogy. In: Soil Mineralogy with Environmental Applications SSSA Book Series no. 7.
Montmorillonite
PeatCanadian peat
Sphagnum moss peat• 75% Sphagnum species• 90% organic matter
Degree of composition• light > dark > black
British Bryological Society
http://www.mosserlee.com
PeatPhysical
<90% porosityShrink
• Water content• Time
ChemicalpH ≈ 4CEC
Sun Terra
CoirCoir pith
Mesocarp pithy tissueHigh porosityLow Easily Available waterChemical
pH 7CECP and K
Coir
Coir
Sri Lanka and Mexico
Coir
waste product
Coir
Porosity COIR VS PEAT
Surface 41% 12%
Internal 41% 51%
Coir
Porosity COIR VS PEAT
Surface 41% 12%
Internal 41% 51%
Wettability!
CoirFine particle sizeMonitor saltsCa source
Gypsum
Compost
CompostIncrease water holding capacityReproducible?Uniform?Stable?Salt concentration
PoultryMetals
Swine (Zn)
CompostIncrease water holding capacityReproducible?Uniform?Stable?Salt concentration
PoultryMetals
Swine (Zn)
Moisture Content
0
20
40
60
80
100
0.01 0.1 1 10 100Tension (kPa)
Perc
ent v
olum
e
Peat BarkCoir Perlite
RAW
Pine Bark
0%
20%
40%
60%
80%
100%
Con
tain
er V
olum
e
Aged PB PB: 30% Perlite PB: 10% Peat
UnavailableWaterAvailableWaterAir
Solid
Mixtures
37%
Pine Bark
0%
20%
40%
60%
80%
100%
Con
tain
er V
olum
e
Aged PB PB: 30% Perlite PB: 10% Peat
UnavailableWaterAvailableWaterAir
Solid
Mixtures
37%
Inc. Air Space Inc. Available water
Clay amended pine bark
PRACTICALAPPLICATION
Physical PropertiesClay rate
0.25 to 0.85 mm LVM0% to 24% (by vol.)
• 4% incrementsPoromoter15-bar extraction
Clay Rate
0
20
40
60
80
100
0 4 8 12 16 20 24
Vol
ume
(%)
Mineral amendment rate (% vol.)
PorometerResults
Clay Rate
0
20
40
60
80
100
0 4 8 12 16 20 24
Vol
ume
(%)
Mineral amendment rate (% vol.)
Container Capacity
Air space
Clay Rate
0
20
40
60
80
100
0 4 8 12 16 20 24
Vol
ume
(%)
Mineral amendment rate (% vol.)
Container Capacity
Available water
Clay Rate
0
20
40
60
80
100
0 4 8 12 16 20 24
Vol
ume
(%)
Mineral amendment rate (% vol.)
Unavailable water
Available water
Clay Rate
0
20
40
60
80
100
0 4 8 12 16 20 24
Vol
ume
(%)
Mineral amendment rate (% vol.)
Container Capacity
Unavailable water
Air space
Available water
Clay Rate
0
20
40
60
80
100
0 4 8 12 16 20 24
Vol
ume
(%)
Mineral amendment rate (% vol.)
Container Capacity
Unavailable water
Air space
Available water
Normal Range
Clay Rate
0
50
100
150
200
250
300
0 8 12 16 20
Top
dry
mas
s (g
)
Amendment rate (% by vol.)
Clay Rate
0
50
100
150
200
250
300
0 8 12 16 20
Top
dry
mas
s (g
)
Amendment rate (% by vol.)
Max. = 12%
Clay Rate
0
2
4
6
8
10
12
0
0.1
0.2
0.3
0.4
0.5
0 8 12 16 20
Pn (µ
mol
CO
2 m-2
s-1
) gs (µm
ol H2 O
m-2 s
-1)
Amendment rate (% by vol.)
Clay Rate
0
2
4
6
8
10
12
0
0.1
0.2
0.3
0.4
0.5
0 8 12 16 20
Pn (µ
mol
CO
2 m-2
s-1
) gs (µm
ol H2 O
m-2 s
-1)
Amendment rate (% by vol.)
Max. = 11%
Clay Rate
0
0.1
0.2
0.3
0.4
0.5
0
100
200
300
400
500
0 8 12 16 20
g s (µm
ol H
2O m
-2 s
-1)
Water use efficinecy (m
l g-1)
Amendment rate (% by vol.)
Plastic bag method
FIELDQUANTIFICATION
Field QuantificationWhy?
Check Bark supplyExperiment with new componentsAffect of how you pot
Field Quantification
Known container volume
Field Quantification
Fill, pack, remove excess
Field Quantification
Saturate with known volume = total porosity(weight can also be used)
Field Quantification
Drain a known volume = air space
Field Quantification
Container Capacity = total porosity - air space
Field Quantification
Bulk Density = dry weight / container volume
Field QuantificationWhy
Check Bark supplyExperiment with new componentsAffect of how you pot
QUESTIONS